[Space Combat] Smart Shrapnel

[MedwedianPresident]

So the idea is that you launch a rocket from earth. When it reaches the designated orbit, the payload, a container full of "Smart Shrapnel" will open, dispensing the shrapnel. The "Smart Shrapnel" itself consists of thousands and thousands of little bombs attached to a magnet and a computer. When the enemy ship tries to fly through the shrapnel field, the bombs will magnetize themselves, attach themselves to the ship's hull and then detonate, ripping the hull apart effectively. However, when the bombs detect a allied ship, they will instead set their magnet to negative mode and make way for the ship.

[falofonos]

Please provide specifications and diagrams for negative magnet mode.

[MedwedianPresident]

I mean that if it detects an enemy ship, it will magnetize itself in a way so it will be attracted by the ship. But if it is an allied ship, the computer would order the magnet to magnetize itself in a way so it would be repelled.

[Warhorse]

Well, if your enemy obligingly passes within a few inches of your bomblets, at no more than a few fps speed difference, then I suppose it might possibly have some effect. Of course, if you can manage something like that, it would be a whole lot easier and cheaper just to use a warhead that generates regular high-speed dumb shrapnel. Spacecraft are fragile ...

PS --- Magnets do not have a 'negative mode'. The will repel other magnets of similar polarity, but not random objects. Also, weight being at a premium in spacecraft, they are frequently made of light, non-magnetic materials such as aluminum, titanium, or composites.

[MedwedianPresident]

Well, if your enemy obligingly passes within a few inches of your bomblets, at no more than a few fps speed difference, then I suppose it might possibly have some effect. Of course, if you can manage something like that, it would be a whole lot easier and cheaper just to use a warhead that generates regular high-speed dumb shrapnel. Spacecraft are fragile ...

This is not a weapon of immediate action, rather it is a defense system that is deployed in orbit a large amount of time before the orbit is threatened.

PS --- Magnets do not have a 'negative mode'. The will repel other magnets of similar polarity, but not random objects. Also, weight being at a premium in spacecraft, they are frequently made of light, non-magnetic materials such as aluminum, titanium, or composites.

How about the computer would automatically recognize which polarity the targeted part of the ship has?

[Charzy]

No matter how good your computer is, you're not going to make a magnet stick to aluminium.

[Warhorse]

This is not a weapon of immediate action, rather it is a defense system that is deployed in orbit a large amount of time before the orbit is threatened.

So what? It still relies on your opponent being improbably dumb. And there are still cheaper and easier ways to achieve the same effect.

How about the computer would automatically recognize which polarity the targeted part of the ship has?

The point is, the target is not even going to be made of magnetic materials, never mind radiating a magnetic field of whatever polarity.

[rpayne88]

I don't even think you could use explosives in space. The reason being that an explosive is basically a fuel that burns VERY rapidly, producing a pressure wave. If it did have an oxidizer so it could detonate, it would not have a medium to produce a pressure wave to destroy the target. Even if it did somehow produce a pressure wave, how would you make it survive until the target vessel arrived? Most explosives are heat sensitive. Compounds such as C4 need a "primary" explosive to detonate it. (This knowledge is coming from a forensic science class I took in High School.) This primary explosive is heat sensitive. How would you stop the extreme heat from the Sun from detonating the explosives?

Why even bring explosives in the first place. As said above, spacecraft are fragile. Why not go for a kinetic kill vehicle.

[magnemoe]

Shrapnel and sharped charges work just as well in vacuum. Shrapnel works even better as its no air resistance to slow them down.

However you will not be able to attract yourself to an enemy ship with magnets, unless you are in docking speed and range to it. See mythboosters test of trying to redirect steel bullets just over an magnet, they moved at 300 m/s, magnets needs to be a few meters away to have any effects. At that range you would better off with an claymore mine setup, if the ship is manned you could board. Or just fire an gun on the target from a killometer away with an 300 m/s speed difference.

[zekes]

or use ACTUAL weapons and ships... Plus there is just too much space to put shrapnel in all of it, plus it would drift apart.

[Thiel]

I don't even think you could use explosives in space. The reason being that an explosive is basically a fuel that burns VERY rapidly, producing a pressure wave. If it did have an oxidizer so it could detonate, it would not have a medium to produce a pressure wave to destroy the target. Even if it did somehow produce a pressure wave, how would you make it survive until the target vessel arrived? Most explosives are heat sensitive. Compounds such as C4 need a "primary" explosive to detonate it. (This knowledge is coming from a forensic science class I took in High School.) This primary explosive is heat sensitive. How would you stop the extreme heat from the Sun from detonating the explosives?

While it's true that primers tend to be heat sensitive to some degree they're not that sensitive. Besides they'll presumably be inside the warhead with all the other explosives and a nice steel casing to shield it.

Why even bring explosives in the first place. As said above, spacecraft are fragile. Why not go for a kinetic kill vehicle.

It makes it easier to hit. A unitary KKV needs to make hull contact, a fragmentation warhead just needs to get "close enough".

[Skyler4856]

Sort of like a localized Kessler syndrome

[Seret]

the bombs will magnetize themselves, attach themselves to the ship's hull and then detonate

Spacecraft are built like aircraft, for minimum weight. That means lots of lightweight materials like aluminium and titanium. There would be some ferrous materials in them, but not a lot. And besides, even if you were trying to get your magnet to stick to something like a nice steel car, the effective range of your magnets will be far less than the effective range of your explosives. So why bother trying to stick? Just detect the target is within range and explode.

Your idea in general has a certain amount of merit, you're basically describing a space minefield composed of sensor fused munitions. The military already do similar things with artillery or air laid minefields here on earth. I would modify your idea to be basically a fragmentation warhead with a target detecting device. Something like the warhead and TDD from an IR missile such as a Sidewinder but with a long-term power supply. If it detects anything close it goes bang and slices up the target with it's nice expanding rod frag. Obviously this lacks the IFF part of your idea, but I think that would be difficult to do reliably.

I don't even think you could use explosives in space. The reason being that an explosive is basically a fuel that burns VERY rapidly, producing a pressure wave. If it did have an oxidizer so it could detonate

Not quite. What you're describing is deflagration. Explosives will deflagrate at high temperatures, but that's a different reaction from a proper detonation. Detonation doesn't require an oxidiser, and is a lot more energetic than deflagration. Explosives quite happily work underwater, underground, at high altitude. They don't require atmospheric oxygen so yes, they would work fine in space too.

it would not have a medium to produce a pressure wave to destroy the target.

Explosives generate large amounts of gas when they detonate. It's this gas that produces all the familiar effects (things getting blown apart, fragments being accelerated, people becoming dead). Heat and flame might be great for Hollywood explosions, but in the real world it's a high speed expanding gas cloud that does the work.

how would you make it survive until the target vessel arrived? Most explosives are heat sensitive. Compounds such as C4 need a "primary" explosive to detonate it. (This knowledge is coming from a forensic science class I took in High School.) This primary explosive is heat sensitive. How would you stop the extreme heat from the Sun from detonating the explosives?

Most high explosives are pretty insensitive, they're designed that way to make them relatively immune to fire and safe to handle. Even if you do set fire to them they still might not detonate, they'll just deflagrate (although deflagrating explosives often have enough smash to properly detonate those near to them). Soldiers sometimes use small amounts of plastic explosives for cooking. I've never done it myself, but apparently it burns just like a solid fuel (like the hexamine soldiers normally cook with).

You're right that you tend to use a smaller amount of a more sensitive explosive to initiate them, but it's pressure not heat that sets them off. To initiate a detonation you need to hit the main charge with a pressure wave moving at a high enough speed. Even the primary detonator need not be particularly sensitive to heat, you could simply insulate it and then initiate it electrically.

Edited November 17, 2013 by Seret

[Will Fawkes]

Awsome. You want to have landmines, some of the most deadly and terrifying weapons on earth for the fact they maim thousands (per year) and deny otherwise useful land because clearing them is expensive.

And you want ot put those things into space.

I personally think that's a terrible idea 'smart' munitions or otherwise because intentionally sending up something into space to explode and send all kinds of fragments of itself is just... well... exasperating the space junk problem we already have.

Edit: a statistic.

Edited November 17, 2013 by Will Fawkes

[Seret]

Earth orbit is pretty much depopulated Will, most of the time there are only the six people on the ISS up there and they inhabit a fairly predictable area, so there's very little risk to civilians. I think the problem with cleaning up spent munitions in orbit would mean that it would be sensible to only deploy an orbital minefield on a decaying orbit anyway. Otherwise it would be a nightmare to go grab them later. It'd add a bit much complexity to have them deorbit themselves reliably, it'd be far easier to simply deploy them so they were only active for a defined period of time then would automatically renter and burn up.

[DaveofDefeat]

Why not send up a small satellite with basic radar, IFF and a single use gun that will just detect and shoot the enemy's.

[Seret]

Coverage of a larger area? Uncertainty about the location of the target? Harder to counter?

I think your suggestion is totally the way to take out a point target though. Might not even need the gun either, kinetic kill with the actual vehicle itself would work. Depends how confident you are on your terminal guidance. If you reckon you can hit it directly then just go for a kinetic kill, if you're not confident of that then you go for fragmentation/shotgun style approach.